• • Ti3C2Tx MXene gel enables 3D printing of electrodes up to 1 mm thick, eliminating the critical cracking thickness limitation of slurry-coated electrodes (typically <200 µm). This allows mass loadings up to 18.4 mg cm−2, a 5–10× increase over conventional electrodes, directly boosting areal capacity to 7.2 mA h cm−2.
• • At −20 °C, the 3DP MoS3/MXene electrode retains 4.2 mA h cm−2, corresponding to 58% capacity retention relative to room temperature. This low-temperature performance is attributed to the multi-scale porous structure that maintains ion permeability, overcoming the sluggish kinetics that plague thick electrodes in cold environments.
• • The MXene additive serves triple duty—viscosifier, conductive agent, and active material—reducing inactive components. This increases active material fraction and eliminates the need for polymer binders and carbon additives, which typically degrade electrical conductivity and mechanical stability.
• • A full cell using MoS3/MXene anode and Na3V2(PO4)3/MXene cathode achieves 400 Wh kg−1 energy density, demonstrating practical viability for sodium-ion batteries. This performance is competitive with lithium-ion systems and addresses cost and resource concerns.